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1.
The International Symposium on Lipid Science and Health (ISLSH), which was organized annually by Oil Crops Research Institute of Chinese Academy of Agricultural Sciences (OCRI-CAAS) since 2016, has gained a strong reputation and attracted hundreds of delegates from around the world for discussion of lipid research trends and advances every year, to promote research and academic exchanges in the fields of lipid science and health. The 5th International Symposium on lipid Science and Health was successfully held in Wuhan, China, from October 23rd to 25th, 2020, to celebrate the 60th anniversary of OCRI-CAAS. The two-day symposium gathered well-known experts specialized in lipid science to share the current state of lipid research with emphasis on aspects covering: (1) lipid profiling and characterization, (2) lipid preparation and modification, (3) lipid improvement and regulation, and (4) lipid nutrition and health. The symposium was conducted by a combination of on-site and network meeting. More than 250 distinguished delegates from academia and industry participated in the on-site multidisciplinary meeting, and thousands of scholars attended the virtual event. This paper is as a record of the symposium proceedings and a brief summary of the advances and trends in 4 aspects of lipid science and health.  相似文献   
2.
The newly formed extensive flooded land associated with the Three Gorges Reservoir hold great potentials to provide ecosystem services (ESs) for surrounding cities and communities. Conflicting values and conventional management strategies may complicate and inhibit broad-scale decision-making for this novel ecosystem. Public attitudes are a crucial influence in the way this process plays out. This study was conducted to assess how the reservoir bank is perceived by the general public of Chongqing Municipality in terms of importance of riparian ESs, and preference for corresponding landscape design styles through photo-questionnaire interviewing. Although Chongqing citizens know little of the “ecosystem services” concept, they do recognise riparian environmental and ecological benefits especially the bank protection and pollution interception functions, while benefits of habitats for wildlife and flood attenuation were of less concern. Recreational values were least appreciated, which is inconsistent with other studies. This may be attributed to a wider, intensive environmental education in various social media in today’s China. But publicity has been dominated by toxic air, water and soil pollution control rather than the benefits of nature conservation and personal contact with nature. In line with recognition of ESs, there is quite strong preference for the forested design scenario and particularly vegetation components across the socio-demographic spectrum. Overall, socio-demographic variables have very low explanatory power for the perceptual responses. Our study also revealed misunderstandings around riparian functions and a gap between public expectations and special abiotic and biotic prerequisites in restoring novel ecosystems. Finally, we discuss the relevance of this research to urban novel ecosystems in general, and implications for raising public awareness, engaging appropriate public values in sustainable design and management of such ecosystems.  相似文献   
3.
Zn deficiency is one of the leading health problems in children and women of developing countries. Different interventions could be used to overcome malnutrition, but biofortification is most impactful, convenient, sustainable and acceptable intervention. Maize is one of the major crops grown and consumed in the regions with prevalent Zn malnutrition; therefore, this is suitable target for Zn biofortification. Zn biofortification of maize could be achieved through agronomic and genetic approaches. Discussion of agronomic approaches with genetic approaches is prerequisite because soils in developing countries are deficit of Zn and availability of Zn in soils is mandatory for estimating the genetic responses of maize genotypes through genetic approaches. Seed priming, foliar and soil applications are agronomic tools for biofortification, but solo and combined applications of these treatments have different effects on Zn enrichment. Genetic approaches include the increase of Zn bioavailability or increase of kernel Zn concentration. Zn bioavailability could be increased by reducing the anti‐nutritional factors or by increasing the bioavailability enhancers. Kernel Zn concentration could be improved through hybridization and selections, whereas genetically engineered attempts for improving Zn uptake from soil, loading in xylem, remobilization in grains and sequestration in endosperm can further improve the kernel Zn concentration. Key challenges associated with dissemination of Zn biofortified maize are also under discussion in this draft. Current review emphasized all of above‐mentioned contents to provide roadmap for the development of Zn biofortified maize genotypes to curb the global Zn malnutrition.  相似文献   
4.
猪繁殖性能的提高将为养猪业带来巨大的经济效益 ,目前多数育种者将提高猪的繁殖力作为主要育种目标 ,并用数学遗传学方法和分子育种技术对繁殖性状进行改良。  相似文献   
5.
阜康荒漠绿洲土地利用景观格局受自然分异和水土资源开发利用程度的制约 ,通过划分景观样带和选取景观空间格局指标 ,本文重点揭示该区域景观格局的变化及其影响因子。结果表明 :( 1 ) 1 987年至 1 998年间阜康土地利用景观格局变化主要表现为耕地面积在洪积扇上增加 ,在冲积平原上下降 ;荒地则刚好相反。林地面积在低山丘陵带和洪积扇带下降 ,在冲积平原上没有变化。牧草地面积在低山丘陵带上升 ,其他各带均下降。城镇面积在各样带上都有所增加 ,水域各带基本不变。 ( 2 )低山丘陵带和洪积扇带景观多样性和均匀度下降 ,优势度上升 ;而冲积平原则多样性和均匀度上升 ,优势度下降。景观破碎度有增加的趋势 ,表明了人为影响的不断增强。  相似文献   
6.
Landscape modeling requires the delineation of system boundaries and interior features. Quite often, these components are complex and difficult to accurately represent. A rectangular grid is used to represent the study and adjacent non-study areas in most cases. When the non-study area occupies a large portion of the grid, computer memory is wasted, and computational time increases. An elliptical grid generator for non-orthogonal curvilinear coordinates is used to generate a boundary-fitted grid for a landscape model. In a boundary-fitted grid coordinate system, one coordinate axis follows the landscape domain boundary and is non-orthogonal to the second axis. The boundary-fitted grid uses elliptic partial differential equations to distribute grid points inside the landscape domain. Although the boundary-fitted grid follows the domain boundary, the grid pattern and point allocation remain structured. Thus, a landscape model can use a boundary-fitted grid without changing the model’s data structure or the computational scheme. In this study, a boundary-fitted grid and a raster-based grid were applied to the Everglades Landscape Fire Model. Use of the boundary-fitted grid decreased model simulation time by about one fifth and computer storage by 58% relative to the raster-based grid. Also, the linear characteristics of interior geographical features such as rivers and airboat trails were preserved by the boundary-fitted grid, but not by the raster-based grid. This preservation provided a more reasonable base map for simulating ecological processes, such as fire across heterogenous landscapes.  相似文献   
7.
刘国军  徐强 《森林工程》2004,20(4):40-41
通过研制稀有金属钨丝合股设备 ,并根据实际运行情况 ,对设备进行改造 ,完善了其加工性能 ,提高了产品的经济效益  相似文献   
8.
安远县国营林场根据生态学原理,对阔叶次生林进行改造,把天然更新和人工改造更新有机的结合起来。通过改造可很快的形成多树种的混交林,林木材积生长提高115%~219%,土壤物理性比杉木纯林好,土壤贮水量比杉木纯林提高57%~92%,有良好的生态经济效益。实践证明,次生林改造是次生林经营的重要措施,是加速培育森林资源的好途径。  相似文献   
9.
农七师车排子垦区柳沟灌区,原有柳沟一、二、三场,面积59万余亩。由于盐碱危害,生产状况和经济状况日益恶化,难以自立。在60年代初,与原25团合并,成为现今的125团的三个营,近年来进行大规模的盐碱土改良工作,取得了显著的效果。基本情况改良效果的观测主要在二营(原柳沟三场)进行,二营面积10.67万亩,可耕地8.85万亩,位于灌区南部、天山北麓,奎屯河与四棵树之间。区内由南向北倾斜,地势低平,坡降1-3‰,土壤多为粉粒中壤和重壤,1-2米以下,广泛分布着红棕色粘土层,因而地下水迳流呈封闭状态,极其不畅,主要靠地面蒸发和植物蒸腾维持平衡。地下水埋深1-1.5米;低洼区接近地面。矿化度20-30克/升,最高达88.45克/升。高矿化与高水位成为土壤盐渍化迅速发展的根本原因。  相似文献   
10.
近年来,我国的景观植物产业得到了很大发展,但仍存在很多问题,为了解决这些问题,我们开发了景观植物信息查询系统(简称LPIIS)。LPIIS的构建包括后台数据库和管理系统2部分,以Microsoft Access开发后台景观植物数据库,实现各种零散的景观植物数据资料的数字化;采用面向对象的开发语言VB进行信息系统的界面设计和系统集成,实现了人性化的界面,操作更为方便。LPIIS的出现改变了过去景观植物信息管理的手工方式,具有可视化人性化的界面、提供多媒体信息、数据的维护和更新具有继承性、后台数据库可方便的移植于网络等特点。  相似文献   
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