Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
MAN Duoqing
LI Delu
LIU Mingcheng
ZHANG Dekui
TANG Jinnian,CHEN Fang
FU Guiquan
YANG Xuemei
DING feng
Abstract： Through eco-measurement and research at the Xishawo desert pasture in Minqin for 60 a, it was foundthat desert vegetation flora has experienced four main stages with ground water- table decline, they were thedegraded meadow steppe and Tamarix flora, Tamarix and Nitraria flora, Nitraria and degraded Tamarix flora, andNitraria flora, the plant diversity and coverage dcreased in the processing, eco- degradation and desertificationdeveloped remarkably; with rain-fed area enlargement, desert herbal plants grew when precipitation was higher inthe year, the plant diversity and coverage increased, and vice versa; some desert shrubs were relatively stable, itspopulation growth and development improved when precipitation was over 140 mm, 100-140 mm for basicgrowth, and < 100 mm degraded gradually; most plant species of windbreak and sand- fixation afforestationdegraded under drought conditions, Haloxylon ammodendron had strong eco- adaptability as an introducedspecies, it has developed into the biggest man-made windbreak and sand-fixation forest in Minqin desert areas, itsbig density and drought land were the main reasons for degradation, and sustainability could be increased underlow density afforestation according to local plant carry capacity. Recently, with the integrated programimplementation in the Shiyang River watershed area, eco- water has been increased, groundwater table hasincreased in some surroundings, some micro-wetlands have formed, original desert meadow steppe has reoccured,and their ecosystems are developing positively; however, ground water table still reduces slowly in most desertareas, and desertification has developed.
Subjects: Library Science，Information Science >> Information Science submitted time 2023-07-09 Cooperative journals: 《中国科学院院刊》
Abstract： Biotech seed industry is a strategic core industry. Biotechnology combined with digital technology has promoted the seed industry into an intelligent era, and the breeding paradigm has changed from “experimental selection” to “computational selection”. Biotech seed industry has become a research and development intensive industry, and the market is highly concentrated, which is controlled by large multinational enterprises. The scientific and technological output of China and the United States is in the first echelon, and the number of papers and authorized patents ranks among the top two in the world. From the perspective of core competitiveness, the United States is a global leader with monopoly advantages in original basic research and key technology. China has made great progress in the application of breeding technology, but it still needs to breakthrough in basic theory research, key technology development, and high value seed product.
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-05-11 Cooperative journals: 《中国全科医学》
Abstract： Background The surgical protocols and prognosis of esophageal squamous cell carcinoma（ESCC） patients influenced by the status of lymph node metastasis. It is necessary to identify risk factors that can predict lymph node metastasis to assist in clinical treatment. Objective To investigate the predict value of tumor budding（TB）and tumor-infiltrating lymphocytes（TILs）on lymph node metastasis（LNM）in patients with ESCC. Methods A total of 124 patients with ESCC who underwent radical resection and retained paraffin-embedded specimens in the Affiliated People's Hospital of Ningbo University from January 2013 to March 2022 were selected as the research subjects. The light microscopy and CK5/6 immunohistochemical staining were used to evaluate the amount of TB and density of TILs. Multivariate Logistic regression analysis was used to explore the influencing factors of lymph node metastasis in patients with ESCC and the receiver operating characteristic（ROC）curve was plotted to investigate the predictive value of TB and TILs for lymph node metastasis in patients with ESCC. Results Multivariate Logistic regression analysis showed that TB（OR=20.078，P<0.001），TILs（OR=0.218，P=0.008），and intravascular tumor thrombus（OR=28.609，P<0.001）were influencing factors for lymph node metastasis. The area under ROC curve（AUC）for TB and TILs to predict lymph node metastasis in patients with ESCC was 0.835〔95%CI（0.763，0.907）〕and 0.656〔95%CI（0.558，0.753）〕，respectively. Conclusions High-grade TB and low-density TILs were influencing factors for lymph node metastasis，TB grade and density of TILs has good diagnostic efficacy in predicting lymph node metastasis in patients with ESCC.
Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] This paper aims to extract the tacit knowledge from the massive literatures by constructing a two-mode complex network model. [Method/process] Through the NetworkX complex network toolkit, a two-mode complex network model was constructed based on the co-occurrence relationship of any two nodes. The direct relationship between nodes and nodes was extracted by weighting the co-occurrence relationship of nodes in the network model, calculating the topology information of the network and AP clustering. The most appropriate prediction algorithm was selected by using AUC method to evaluate the four link prediction algorithms, such as AA, JC, wAA and wJC. The tacit knowledge was predicted by the most appropriate prediction algorithm from the complex networks. [Result/conclusion] The results showed that the wAA link prediction algorithm was the optimal link prediction algorithm. The two mode complex network model, indicators and method system were effective in drug target mining in the Chemical Abstracts Service database. The next step is to try in other databases or other research fields to further verify the generality and effectiveness of the model.
Subjects: Library Science，Information Science >> Information Science submitted time 2023-04-01 Cooperative journals: 《图书情报工作》
Abstract： [Purpose/significance] This paper try to propose a scientific, effective and reusable method to identify key technologies based on the perspective of intelligence research. It aims to provide information support for nation, regions, enterprises and innovative institutions to discover, deploy and promote the prospective R&D of key technologies.[Method/process] Based on the definition of key technology and its types, this paper used K-means++ algorithm to cluster scientific papers to identify hotspot technologies. Then it used the hotspot technologies as nodes to construct and visualize complex network through secondary clustering and Gephi. Structural holes theory was adopted to analysis the network and attributes of nodes, and thereby selected generic technologies. Link prediction algorithm was used to predict the missing edges in the network according to the structure, and we can identify the potential emerging technologies based on the phenomenon of cross-fusion of hot technologies to promote the formation of innovative technologies.[Result/conclusion] Taking the Intelligent Manufacturing as an example to carry out empirical research on the method, and validated the operability and effectiveness of the method through national authoritative documents and literature research.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： Innovation-driven development has been a new development direction among global economies. Innovation statistics provide a new platform for understanding the interaction of science, technology, and economy. The practice of innovation statistics in developed countries has formed a good standard system and international standard. China, based on international practice, has established a new system of innovation statistics and laid the foundation for further promoting the strategy of innovation-driven development. In the future, China will still need to take international standards as the base, understand the development reality of the country, respect the law of statistics, pay attention to the statistics and research of innovative talents, and promote the construction of the innovation statistics system.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-18 Cooperative journals: 《材料研究学报》
Abstract： Star shaped block copolymer POSS-(PMMA-b-PS)8 was synthesized by a two step process of atom transfer radical polymerization (ATRP) with eight functionalized polyhedral oligomeric silisesquioxane POSS-(Cl)8 as core and poly(methyl methacrylate-b-polystyrene) as arm. The POSS-(PMMA-b-PS)8 was then sulfonation treated to produce hybrid polymer POSS-(PMMA-b-SPS)8, which was finally used as the polymer matrix for making proton exchange membranes (PEMs). The examination of conductivity as function of relative humidity for PEMs of high and low hydration status respectively indicated that with longer SPS block length exhibited higher proton conductivity for the PEMs of low hydration status with the same λ i.e. the number of water molecular coupled to sulfonic acid groups. TGA analysis showed that two kinds of PEM all exhibited higher water retention capacity and higher initial decomposition temperature. A well-connected ionic domains in PEM with longer SPS block could be observed by transmis-sion electron microscopy (TEM) and atomic force microscopy (AFM). The features of molecules motion of chain segments and spins relaxation time T2 for the PEMs of low hydration status were analyzed by low field nuclear magnetic resonance, and it is found that the well connected ionic domains could be observed also in the PEMs with longer SPS block, which exhibited higher proton spin-diffusion coefficient, therewith higher proton conductivity by low relative humidity.
Subjects: Biology >> Botany >> Applied botany submitted time 2019-02-25 Cooperative journals: 《广西植物》
Abstract：采用 HPLC 法，分析测定一年生罂粟植株体开花后不同生育期根、茎、叶、果壳中蒂巴因含量变化，通过研究罂粟体内蒂巴因的变化规律和水氮耦合对蒂巴因的影响，为合理开发和管理这一特种药源植物提供依据。结果显示：一年生罂粟植株体蒂巴因含量的变化范围在果壳中为 1.81%～4.54%，成熟期达到最高；叶片中为 0.30%～0.68%，膨大后期最高，采收期最低；根中为 0.03～0.28%，膨大前期最高，采收期最低；茎秆中为 0.23%～0.60%，呈递减趋势，采收期最低，茎上、中、下部的蒂巴因含量的变化范围分别为 0.42%～0.97%、0.15%～0.60%、0.13%～0.37%。滴灌量和施氮量对一年生罂粟果壳中蒂巴因含量的影响差异显著罂粟壳质量最佳的水氮偶合条件为 I130Ｎ14，即滴灌量为 130 m3·(667 m2)-1，施氮量为 14kg·(667 m2)-1时，蒂巴因含量达最高。
Subjects: Biology >> Zoology submitted time 2018-12-25 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究苎麻替代不同比例苜蓿对波尔山羊生长性能、血清生化指标及养分表观消化率的影响。选择体重[（17.51±1.79） kg]相近的3月龄左右波尔山羊羔羊75只，采用单因子试验设计，随机分为5组，每组5个重复，每个重复3只羊。对照组饲喂基础饲粮，4个试验组分别饲喂以苎麻等量替代基础饲粮中25%（试验Ⅰ组）、50%（试验Ⅱ组）、75%（试验Ⅲ组）和100%（试验Ⅳ组）苜蓿的试验饲粮。预试期15 d，正试期75 d。于正试期第60天开始对试验羔羊进行为期4 d的消化代谢试验，收集羔羊粪便，在试验结束当天采集血液样品。结果显示：1）苎麻的粗蛋白质、粗脂肪、钙、中性洗涤纤维、酸性洗涤纤维和粗灰分的含量均高于苜蓿。2）试验Ⅰ组、试验Ⅱ组和试验Ⅲ组山羊的平均日增重与对照组相比分别下降了1.93%、6.16%和20.74%，差异不显著（P>0.05)；试验Ⅳ组山羊的平均日增重与对照组和试验Ⅰ组相比分别降低了27.38%和25.96%，差异显著（P0.05)；各个试验组山羊血清中游离三碘甲状原氨酸含量较对照组有不同程度的下降，其中试验Ⅱ组、试验Ⅲ组和试验Ⅳ组与对照组的差异达到显著水平（P0.05），但试验Ⅳ组钙的表观消化率与对照组、试验Ⅰ组、试验Ⅱ组和试验Ⅲ组相比分别降低了11.69%（P0.05）。综上，苎麻营养价值较高，可以作为优质饲草部分代替苜蓿在波尔山羊饲粮中高效利用。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究甘氨酸亚铁对断奶仔猪生长性能、铁表观消化率及血清铁相关指标的影响。试验选取12头“杜×长×大”（28±1）日龄断奶仔猪，根据体重、健康状况等均衡分布原则分为2组，每组6个重复，每个重复1头仔猪，单个饲养于消化代谢笼。试验分为2个阶段，第1阶段：2组均饲喂缺铁基础饲粮10 d，使仔猪处于临近贫血状态；第2阶段：对照组在缺铁基础饲粮中额外添加100 mg/kg的硫酸亚铁（以铁计），试验组额外添加100 mg/kg的甘氨酸亚铁（以铁计），试验期10 d。结果表明：与添加硫酸亚铁相比，饲粮添加甘氨酸亚铁有降低仔猪料重比的趋势(P＜0.10)，降低了4.57%，但对仔猪的平均日增重、平均日采食量无显著差异(P>0.10)；饲粮添加甘氨酸亚铁能显著降低粪中的铁排出量和铁排出总量(P＜0.05)，分别降低了23.11%和22.09%；饲粮添加甘氨酸亚铁能极显著提高铁表观消化率和表观代谢率(P＜0.01)，分别提高了13.34%和22.42%；同时，饲粮添加甘氨酸亚铁能显著提高血清中的铁饱和度和血液中的铁含量(P＜0.05)。综上，甘氨酸亚铁可提高断奶仔猪的生长性能，提高血液铁含量，改善仔猪铁代谢状况，降低粪便铁排出量，是一种绿色高效的新型补铁剂。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究饲粮添加维生素E和酵母硒对黄羽肉种鸡产蛋性能、孵化性能及蛋中维生素E和硒（Se）沉积量的影响。试验采用3×3双因子设计，设3个维生素E水平（0、20、40 IU/kg）和3个Se水平（0、0.15、0.30 mg/kg)。选用32周龄快大型岭南黄羽肉鸡父母代种母鸡864只，根据产蛋率和体重一致性原则随机分成9个组，分别为VE0Se0组、VE0Se0.15组、VE0Se0.30组、VE20Se0组、VE20Se0.15组、VE20Se0.30组、VE40Se0组、VE40Se0.15组和VE40Se0.30组，每组6个重复，每个重复16只鸡。试验期8周。结果表明：1）饲粮中维生素E和Se水平对黄羽肉种鸡的体增重、平均日产蛋量、料蛋比、平均蛋重、产蛋率、破蛋率和不合格蛋率均无显著影响（P>0.05）。2）饲粮中维生素E和Se水平对黄羽肉种鸡的蛋长径、蛋短径、蛋白高度、蛋黄颜色、哈氏单位、蛋黄重、蛋壳重和蛋壳厚度均无显著影响（P>0.05）。3）饲粮中维生素E和Se水平对黄羽肉种鸡的健雏出壳重、孵化率、弱雏率和受精率均无显著影响（P>0.05）。4）饲粮中维生素E水平对黄羽肉种鸡血浆MDA含量有显著影响（P<0.05），随饲粮中维生素E水平的升高血浆MDA含量呈降低趋势，其中维生素E水平为40 IU/kg时血浆MDA含量显著低于0 IU/kg时（P<0.05）；饲粮中维生素E和Se水平对血浆MDA含量有显著交互作用（P<0.05），其中VE40Se0组的血浆MDA含量显著低于VE0Se0.15和VE0Se0.30组（P<0.05）。5）随饲粮中维生素E和Se水平的升高，黄羽肉种鸡蛋中维生素E和Se含量显著增加（P<0.05）；饲粮中维生素E和Se水平对蛋中维生素E和Se含量有显著交互作用（P<0.05）。结果提示，维生素E可以提高黄羽肉种鸡的抗氧化水平，饲粮中维生素E和Se水平可以显著影响蛋中维生素E和Se的含量；建议在无任何应激因素刺激和不使用Se缺乏地区饲料原料的情况下，黄羽肉种鸡玉米豆粕型饲粮可以不用额外添加维生素E和Se。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究不同饲粮精氨酸水平对黄羽肉种鸡繁殖性能的影响。试验选用780只36周龄的黄羽肉种鸡作为试验鸡，采用单因素随机分组试验设计分成5个组（饲粮精氨酸水平分别为0.65%、0.80%、0.95%、1.10%和1.25%），每组6个重复，每个重复26只鸡。试验预试验2周，饲喂第1组饲粮；正试期10周。结果表明：饲粮中添加不同水平精氨酸对试验全期种鸡产蛋率、平均蛋重和料蛋比均没有显著影响（P>0.05）。1.10%精氨酸组的产蛋率最高，与0.65%和1.25%精氨酸组相比有提高的趋势（P0.05）。由此可见，适度添加精氨酸一定程度上能提高黄羽肉种鸡产蛋率，增强种蛋蛋壳强度和种鸡抗氧化能力。综合本试验多项指标推荐快大型黄羽肉种鸡产蛋高峰期饲粮中精氨酸水平为1.10%。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究饲粮不同硒添加水平对1～21日龄岭南黄羽肉仔鸡生长性能和抗氧化性能的影响，以探讨快大型岭南黄羽肉仔鸡饲养前期的饲粮硒适宜供给量。选用1日龄健康、发育良好的快大型岭南黄羽肉公雏鸡1 200只，根据体重随机分为5个组，每组6个重复，每个重复40只鸡，试验1组（对照组）饲喂基础饲粮（硒水平为0.039 mg/kg），试验2~5组饲粮在基础饲粮中分别添加0.075、0.150、0.225和0.300 mg/kg硒，试验期21 d。结果表明：本试验条件下：1）饲粮添加0.300 mg/kg硒显著降低1～21日龄岭南黄羽肉仔鸡的末重（P<0.05），显著提高料重比（P<0.05），且0.300 mg/kg硒添加组的平均日增重显著低于其他各水平硒添加组（P<0.05）。2）与对照组相比，饲粮添加0.075和0.150 mg/kg硒显著提高21日龄岭南黄羽肉仔鸡的血浆谷胱甘肽过氧化物酶（GSH-Px）活性（P<0.05），饲粮添加0.225和0.300 mg/kg硒显著降低血浆MDA含量（P<0.05）。各水平硒添加组的红细胞GSH-Px活性均显著高于对照组（P<0.05）。3）与对照组相比，饲粮添加0.075、0.150和0.225 mg/kg硒显著提高21日龄岭南黄羽肉仔鸡的肝脏GSH-Px活性（P<0.05），0.075和0.150 mg/kg硒添加组的肝脏MDA含量显著低于对照组和0.300 mg/kg硒添加组（P<0.05）。综合考虑，为获得较好生长性能和抗氧化性能，1～21日龄岭南黄羽肉仔鸡饲粮硒适宜添加水平为0.075 mg/kg，基础饲粮中硒水平为0.039 mg/kg，则1～21日龄岭南黄羽肉仔鸡饲粮硒适宜供给量为0.114 mg/kg；以肝脏MDA含量为依据，通过非线性回归分析估测得到1～21日龄岭南黄羽肉仔鸡饲粮硒适宜供给量为0.129 mg/kg。
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