Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： One of the burning questions of food security in current China is how to produce sufficient forage products and animal feeds. The limited arable land has to be devoted to cereal production, and exploring more terrestrial land is a prerequisite for the sustainable forage production and the development of grass-based livestock husbandry. Bohai rim is consist of coastal line of the North China Plain, which has a significant amount of medium-low yielding fields and unutilized saline-alkali land as well as intensive livestock production. In this study, a new concept of “Coastal Grass Belt”, proposed by LI Zhensheng, an academician of Chinese Academy of Sciences (CAS), was introduced, which addresses how to develop grass/forage farming system according to the severity of salinity. This concept can not only improve soil quality but also provide sufficient forage for livestock. Meanwhile, the concept is also aligned with China’s national strategies of storing grain in land and in agricultural technology to ensure the self-sufficiency of important agricultural products and the integration of the security of land and marine ecosystems. This paper provides a detailed description of the “Coastal Grass Belt” concept, elaborates its goals, key scientific issues and innovative modes, and analyzes the ecological environmental and economic-industrial benefits. Finally, the much-needed innovation platforms, agro-industry modes and policies for the development of “Coastal Grass Belt” are discussed.
Subjects: Other Disciplines >> Synthetic discipline submitted time 2023-03-28 Cooperative journals: 《中国科学院院刊》
Abstract： The Yellow River Delta is the world’s youngest delta and new land, also the youngest ecosystem. Its ecological environment is fragile, and the interaction among the river, the sea, and the land forms a unique geographical environment. The salinization of land and the wide distribution of saline land are two of the main features of the region, and agriculture is one of the leading industries in the region. Agricultural development is related to the efficient use and rational distribution of water resources in this area, related to the protection of the estuary wetland and the ecological environment of the whole region, and related to the efficient development and safety of land resources. It is also about the overall development of land and sea, as well as about the revitalization of the countryside. Therefore, the high quality development of saline agriculture is the important part of sustainable development of the region, while the development of high-quality agriculture in saline land is an important challenge. Based on the major strategic needs of the country, the current situation, and major problems of the development of the Yellow River Delta, this study puts forward a new model of efficient agricultural development in the saline-alkali areas of the Yellow River Delta, as well as some suggestions for the future ecological protection and high-quality development of the region. This study is also of great significance for the efficient development of saline land in China.
Subjects: Mechanics >> Applied Mechanics submitted time 2023-03-20 Cooperative journals: 《应用力学学报》
Abstract： The high-level rocket lift-off noise induced by the hypersonic jet has adverse impacts on thestructural security and equipment reliability of the rocket ;therefore , it is of great significance to make theprediction and reduction of high-speed jet noise environment. A numerical analysis method based on de-tached eddy simulation ( DES) turbulence model and combined transport equation, discrete phase model(DPM) and FW-H equation was established to calculate the noise of multi-components rocket jet and wa-ter considering evaporation inserts multi-components high speed jet. The prediction pf hypersonic jet flowcondition and noise environment of liquid rocket engine was completed.'The results show that the eror be-tween the predicted results and experimental results of overall sound pressure level of probes is within�3 dB.Furthermore , the annular water inserts noise reduction system was designed , the noise reductionlaw of water involved in high Mach number jet , considering evaporation effect and influence of complex deflector duct configuration , was studied , which reveals that shearing effect , momentum transfer and evapora-tion are important incentives for noise reduction.Besides , the noise suppression effect increases monoton-ously with the increase of mass flow rate , and increases first and then decreases with the increase of inter-vention angle.This study is of great importance in design and engineering of the water inserts system.
Subjects: Medicine, Pharmacy >> Preclinical Medicine submitted time 2021-03-09
Abstract： Objective To explore the possibility of establishing a rabbit model of common carotid artery-external jugular vein arterivenous fistula with modified no-touch technique. Methods 10 male New Zealand rabbits were randomly divided into experimental group and sham operation group.Common carotid artery-external jugular vein arterivenous fistulas were created by the modified no-touch technique in experimental group, which means the perivenous vascular tissue was not stripped off in the operation.And the vessels were not anastomosed in sham operation group. At 14 days after surgery, We used Doppler Ultrasound to evaluate the changes of arterivenous fistula vascular inner diameter and blood-flow spectrum.We used hematoxylin-eosin (H-E) staining to observe the changes of intima thickness. And we took the blood samples from the rabbit’s external jugular vein for blood gas experiment. Results In experimental group, all fistulas were successfully established.100% success rate.14 days after surgery,Doppler ultrasound showed that external jugular vein was significantly expanded(P=0.016) and peak systolic velocity(PSV) was significantly increased in experimental group （P=0.015）. Compared with sham operation group, ultrasonographic examination of the common carotid artery and external jugular vein at 14 days after surgery showed obvious dilation of inner diameter and significantly increased of peak systolic velocity(PSV) in experimental group. The blood-flow spectrum of the common carotid artery and external jugular vein showed spiral laminar flow. H-E staining examination showed that elastic membrane of external jugular vein was destroyed and intima thickness was significantly increased in experimental group(P<0.001). Moreover, the PO2 in the blood of the external jugular vein in experimental group was significantly higher（P=0.006）.Conclusion The modified no-touch technique can successfully establish rabbit common carotid artery-external jugular vein arterivenous [Abstract]Objective To explore the possibility of establishing a rabbit model of common carotid artery-external jugular vein arterivenous fistula with modified no-touch technique. Methods 10 male New Zealand rabbits were randomly divided into experimental group and sham operation group.Common carotid artery-external jugular vein arterivenous fistulas were created by the modified no-touch technique in experimental group, which means the perivenous vascular tissue was not stripped off in the operation.And the vessels were not anastomosed in sham operation group. At 14 days after surgery, We used Doppler Ultrasound to evaluate the changes of arterivenous fistula vascular inner diameter and blood-flow spectrum.We used hematoxylin-eosin (H-E) staining to observe the changes of intima thickness. And we took the blood samples from the rabbit’s external jugular vein for blood gas experiment. Results In experimental group, all fistulas were successfully established.100% success rate.14 days after surgery,Doppler ultrasound showed that external jugular vein was significantly expanded(P=0.016) and peak systolic velocity(PSV) was significantly increased in experimental group （P=0.015）. Compared with sham operation group, ultrasonographic examination of the common carotid artery and external jugular vein at 14 days after surgery showed obvious dilation of inner diameter and significantly increased of peak systolic velocity(PSV) in experimental group. The blood-flow spectrum of the common carotid artery and external jugular vein showed spiral laminar flow. H-E staining examination showed that elastic membrane of external jugular vein was destroyed and intima thickness was significantly increased in experimental group(P<0.001). Moreover, the PO2 in the blood of the external jugular vein in experimental group was significantly higher（P=0.006）.Conclusion The modified no-touch technique can successfully establish rabbit common carotid artery-external jugular vein arterivenous fistula.This model has an ideal success rate and good repeatability, which provides an ideal animal model for further research on the application of modified no-touch technique in arteriovenous fistula surgery.fistula.This model has an ideal success rate and good repeatability, which provides an ideal animal model for further research on the application of modified no-touch technique in arteriovenous fistula surgery. " " "
Peer Review Status:
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Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2021-03-08
Abstract：
Peer Review Status:Awaiting Review
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究3~6月龄伊犁马肠道微生物群落的多样性，揭示断奶前马驹肠道菌群演替的规律，从微生物学角度为此阶段马驹生长发育及肠道健康提供理论依据。试验选取平均体重为（89.75±8.81） kg、出生日期相同的3月龄伊犁马5匹，进行为期90 d的饲养试验。分别在试验的第0天(即试验开始的前1天)、第30天、第60天、第90天采集马驹粪便样品，从每份样品中提取微生物基因组总DNA，采用Illumina HiSeq测序技术检测样品微生物群落多样性。结果显示：1）对5匹马驹的20份粪样进行测序，共获得有效序列数157 665条，获得平均操作分类单元（OTUs）1 117个。2）马驹粪便中微生物群落α多样性指数（ACE、Chao1、Shannon和Simpson指数）随着马驹月龄的增加呈波动性变化，但各时间点之间均无显著性变化（P＞0.05）。3）在门水平上，马驹粪便中10大优势菌分别为厚壁菌门（Firmicutes）、拟杆菌门（Bacteroidetes）、变形菌门（Proteobacteria）、疣微菌门（Verrucomicrobia）、螺旋体菌门（Spirochaetes）、梭杆菌门（Fusobacteria）、无壁菌门（Tenericutes）、放线菌门（Actinobacteria）、TM7、广古菌门（Euryarchaeota），其中以厚壁菌门、拟杆菌门、变形菌门及疣微菌门的丰度较高；在科水平上，马驹粪便中10大优势菌分别为芽孢杆菌科（Bacillaceae）、莫拉氏菌科（Moraxellaceae）、动球菌科（Planococcaceae）、肉杆菌科（Carnobacteriaceae）、BS11、RFP12、乳杆菌科（Lactobacillaceae）、瘤胃球菌科（Ruminococcaceae）、毛螺旋菌科（Lachnospiraceae）、紫单胞菌科（Porphyromonadaceae）；在属水平上，马驹粪便中10大优势菌属分别为不动杆菌属（Acinetobacter）、德库菌属（Desemzia）、乳杆菌属（Lactobacillus）、Ureibacillus、Paludibacter、芽孢杆菌属（Bacillus）、埃希式杆菌属（Escherichia）、肉食杆菌属（Carnobacterium）、密螺旋体属（Treponema）、艰难杆菌属（Mogibacterium）。由此得出，采用Illumina HiSeq测序技术能够准确地对3~6月龄伊犁马肠道微生物群落进行分类研究；厚壁菌门、拟杆菌门、变形菌门、疣微菌门是3~6月龄伊犁马肠道内的优势菌门。
Subjects: Biology >> Zoology submitted time 2017-10-23 Cooperative journals: 《动物营养学报》
Abstract：本试验旨在研究碘醚柳胺驱虫剂对6月龄伊犁马驹营养物质消化代谢及生长发育的影响。试验选取在同一草场饲养的6月龄（出生日期±5 d）、平均体重为（117.60±15.84） kg的伊犁马公马马驹10匹，在相同的饲喂条件下随机分为2组，每组5匹，分别为对照组和试验组。试验组马驹灌服碘醚柳胺混悬液驱虫剂驱虫，每匹14 mL，对照组马驹不进行驱虫。驱虫后，进行为期20 d的消化代谢试验，其中预试期15 d，正试期5 d。结果显示：碘醚柳胺驱虫对马驹各营养物质摄入量、消化量、排出量和消化率均没有产生显著影响（P＞0.05），但试验组中性洗涤纤维、酸性洗涤纤维、钙消化率分别比对照组高18.17%、16.37%、17.36%；试验组马驹氮的沉积量和沉积率分别比对照组高65.90%（P＜0.05）、73.20%（P＜0.05）；试验组马驹体高和胸围的总增长分别比对照组高123.58%（P＜0.05）和48.31%（P＜0.05）。因此，碘醚柳胺驱虫对6月龄伊犁马营养物质消化代谢的积极作用主要体现在氮沉积量和沉积率的增加以及体高和胸围的增长上。
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