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Vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception

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International Journal of Ophthalmology(English edition) 2013年第2期6卷 198-203页

作者： shan-shan yang Tao Jiang Department of Ophthalmology the Affiliated Hospital of Medical College Qingdao University

AIM: To evaluate the efficacy of surgical treatment of vitrectomy combined with silicone oil tamponade in the treatment of severely traumatized eyes with the visual acuity of no light perception (NLP).METHODS: This was a retrospective uncontrolled interventional case-series of 19 patients of severely traumatized eyes with NLP who underwent vitrectomy surgery at the Affiliated Hospital of Medical College, Qingdao University (Qingdao, China) during a 3-year period. We recorded perioperative factors with the potential to influence functional outcome including duration from the injury to intervention; causes for ocular trauma; open globe or closed globe injury; grade of vitreous hemorrhage; grade of endophthalmitis; grade of retinal detachment; size and location of intraocular foreign body (IOFB); extent and position of retinal defect; grade of proliferative vitreoretinopathy (PVR); type of surgery; perioperative complications and tamponade agent. The follow-up time was from 3 to 18 months, and the mean time was 12 ***: After a mean follow-up period of 12 months (3-18 months) 10.53% (2/19) of eyes had visual acuity of between 20/60 and 20/400, 52.63% (10/19) had visual acuity less than 20/400 but more than NLP, and 36.84% (7/19) remained NLP. Visual acuity was improved from NLP to light perception (LP) or better in 63.16% (12/19) of eyes and the rate of complete retinal reattachment was 73.68% (14/19). Good visual acuity all resulted from those patients of blunt trauma with intact eyewall (closed globe injury). The perioperative factors of poor visual acuity prognosis included delayed intervention; open globe injury; endophthalmitis; severe retinal detachment; large IOFB; macular defect; a wide range of retinal defects andsevere ***: The main reasons of NLP after ocular trauma are severe vitreous hemorrhage opacity; refractive media opacity; retinal detachment; retinal and uveal damages and defects, especially defects of the macula; PVR and endopht

关键词： vitrectomy silicone oil tamponade severely traumatized eyes no light perception

Modelling the crop yield gap with a remote sensing-based process model:A case study of winter wheat in the North China Plain

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Journal of Integrative Agriculture 2023年第10期22卷 2993-3005页

作者： yang Xu ZHANG Jia-hua yang shan-shan WANG Jing-wen BAI Yun ZHANG Sha Research Center for Remote Sensing and Digital Earth College of Computer Science and TechnologyQingdao UniversityQingdao 266071P.R.China Aerospace Information Research Institute Chinese Academy of SciencesBeijing 100094P.R.China

Understanding the spatial distribution of the crop yield gap(YG)is essential for improving crop *** studies have typically focused on the site scale,which may lead to considerable uncertainties when scaled to the regional *** mitigate this issue,this study used a process-based and remote sensing driven crop yield model for winter wheat(PRYM-Wheat),which was derived from the boreal ecosystem productivity simulator(BEPS),to simulate the YG of winter wheat in the North China Plain from 2015 to *** validation based on statistical yield data revealed good performance of the PRYM-Wheat Model in simulating winter wheat actual yield(Ya).The distribution of Ya across the North China Plain showed great heterogeneity,decreasing from southeast to *** remote sensing-estimated results show that the average YG of the study area was 6400.6 kg ha^(–1).The YG of Jiangsu Province was the largest,at7307.4 kg ha^(–1),while the YG of Anhui Province was the smallest,at 5842.1 kg ha^(–1).An analysis of the responses of YG to environmental factors showed no obvious correlation between YG and precipitation,but there was a weak negative correlation between YG and accumulated *** addition,the YG was positively correlated with *** general,studying the specific features of the YG can provide directions for increasing crop yields in the future.

关键词： remote sensing PRYM-Wheat Model yield gap environmental factors North China Plain

Existence and Stability of Static Solutions of the Landau-Lifshitz Equation with Multi-direct Effective Field

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Acta Mathematica Sinica,English Series 2004年第6期20卷 1135-1152页

作者： Bo Ling GUO Gan shan yang Institute of Applied Physics and Computational Mathematics Center for Nonlinear Studies Department of Mathematics Yunnan Nationalities University Graduate School of Chinese Academy of Engineering Physics

We prove the existence of solutions of the static Landau-Lifshitz equation with multi- direct effective field and with Dirichlet boundary condition,and establish the stability of the solution of Landau-Lifshitz equati... 详细信息

关键词： Landau-Lifshitz equation Liapunov stable Multi-direct effective field

Dual Control Methods for a Mixed Control Problem with Optimal Stopping Arising in Optimal Consumption and Investment

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Numerical Mathematics(Theory,Methods and Applications) 2022年第3期15卷 641-661页

作者： Jingtang Ma Jie Xing shan yang School of Mathematics Southwestern University of Finance and EconomicsChengdu 611130China Guiyang Institute for Big Data and Finance Guizhou University of Finance and EconomicsGuiyang 550025China

This paper studies a problem of optimal investment and consumption with early retirement option under constant elasticity variation(CEV)model with finite *** risky assets are involved in the model with one following geometric Brownian motion and the other a CEV *** problem is a kind of two dimensional mixed control and optimal stopping problems with finite *** existence and continuity of the optimal retirement threshold surfaces are proved and the working and retirement regions are characterized ***-squares Monte-Carlo methods are developed to solve this mixed control and optimal stopping *** algorithms are well implemented and the optimal retirement threshold surfaces,optimal investment strategies and the optimal consumptions are drawn via examples.

关键词： Optimal investment and consumption stochastic control with optimal stopping nonlinear free boundary problems least-squares Monte-Carlo methods

Developing a quantitative index system for assessing sustainable forestry management in Heilongjiang Province,China： a case study

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Journal of Forestry Research 2016年第3期27卷 611-619页

作者： Jin-shan yang Feng-you Wang College of Forestry Northeast Forestry UniversityHarbin 150040 China Guizhou University for Nationalities Guiyang 550025 China Department of Forestry Forest Resources Management Service Harbin 150090 Heilongjiang Province China

In this study, we developed a comprehensive index system for forestry sustainability of Heilongjiang Province, which includes forest resources sustainability,sustainable economic development, sustainable social development and sustainable advancement in science and technology. Based on this system and the regional forest development, we further evaluated the sustainability of Heilongjiang Province for year 2008-2013. The results show that even though the regional forestry has been preliminarily on the track of sustainable development, it is fragile. Four indicators, e.g. soil and water retention rate,forest stand growth（per unit area）, the proportion of national investment and the annual carbon sequestration have important impact on the sustainability, with a weight of 39.0 % in all the indicators. We also analyzed the factors hindering the sustainable development. It turns out that soil and water retention rate, forest stand growth（per unit area）,the proportion of science and technology funds, per capita GDP and the proportion of the tertiary industry production are the main factors hindering regional sustainable development, which accounts for 50.94 % of the total obstacle degrees in the system. At last, we discussed how to promote the regional sustainable development from the perspectives of forest resources sustainability, economic development sustainability, society development sustainability and the sustainable advancement of science and technology.

关键词： Regional forestry Sustainable development Index system Empirical analysis

Progress in Mechanism of Astragalus membranaceus and Its Chemical Constituents on Multiple Sclerosis

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Chinese Journal of Integrative Medicine 2023年第1期29卷 89-95页

作者： PENG Yong DENG Xiang yang shan-shan NIE Wei TANG Yan-dan Department of Neurology Affiliated First Hospital of Hunan Traditional Chinese Medical CollegeZhuzhouHunan Province412000China

The primary chemical components of Astragalus membranaceus include polysaccharides,saponins,flavonoids,and amino *** studies have shown that Astragalus membranaceus has multiple functions,including improving immune function and exerting antioxidative,anti-radiation,anti-tumor,antibacterial,antiviral,and hormone-like *** membranaceus and its extracts are widely used in clinical practice because they have obvious therapeutic effects against various autoimmune diseases and relatively less adverse *** sclerosis(MS)is an autoimmune disease of central nervous system(CNS),which mainly caused by immune disorder that leads to inflammatory demyelination,inflammatory cell infiltration,and axonal degeneration in the *** this review,the authors analyzed the clinical manifestations of MS and experimental autoimmune encephalomyelitis(EAE)and focused on the efficacy of Astragalus membranaceus and its chemical components in the treatment of MS/EAE.

关键词： Astragalus membranaceus chemical components multiple sclerosis experimental autoimmune encephalomyelitis immunoregulation

Effects of ammonium exchange and Si/Al ratio on the conversion of methanol to propylene over a novel and large partical size ZSM-5

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Journal of Natural Gas Chemistry 2011年第3期20卷 261-265页

作者： Ruchao Wei Chunyi Li Chaohe yang Honghong shan State Key Laboratory of Heavy Oil Processing China University of Petroleum Qingdao 266555 Shandong China

One type of ZSM-5 zeolite with large partical size was prepared and characterized by XRD, SEM, N2 adsorption-desorption, XRF, Py-IR and NH3-TPD techniques. Effects of ammonium exchange and SiO2/Al2O3 molar ratios on the reaction of methanol to propylene （MTP） over Na-ZSM-5 and H-ZSM-5 zeolites have been studied in a fixed-bed flow reactor under the operating conditions of T = 500 °C, P = 1 atm, and WHSV = 6 h-1. Ammonium exchange led to a rapid decrease in Na content for Na-ZSM-5 zeolite. The reaction results indicated that Na-ZSM-5 and H-ZSM-5 with different SiO2/Al2O3 molar ratios all exhibited high activity for methanol conversion. Ammonium exchange and the decreased SiO2/Al2O3 molar ratio of ZSM-5 zeolite led to an increase both in strong acid sites and weak acid sites. Na-ZSM-5 with high SiO2/Al2O3 molar ratio was favorable for the formation of propylene. The highest propylene selectivity （45.9%） was obtained over Na-ZSM-5 zeolite catalyst with SiO2/Al2O3 molar ratio of 220.

关键词： ZSM-5 MTP propylene ammonium exchange acidity

Hydroclimatic anomalies in China during the post-Laki years and the role ofconcurring El Nino

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Advances in Climate Change Research 2021年第2期12卷 187-198页

作者： GAO Chao-Chao yang Lin-shan LIU Fei Department of Environmental Science Zhejiang UniversityHangzhou310058China Key Laboratory of Tropical Atmosphere‒Ocean System Ministry of Education School of Atmospheric SciencesSun Yat-sen UniversityZhuhai519082China Southern Marine Science and Engineering Guangdong Laboratory Zhuhai519082China

Arctic is warming at an alarming speed causing accelerated melting of Greenland and rising of sea level,and geoengineering by injectingaerosol into stratosphere(SAI)has been proposed as a backup approach to mitigate ***,studies suggest that SAI implementationmay have adverse impacts on global especially monsoon precipitation,and Northern Hemisphere high-latitude injections may have dis-proportionally high effects than tropical *** 1783e1784 CE Laki eruption in Iceland provides an analogy to study the climatic andthe subsequent socioecological responses to Arctic SAI,and China possesses a rich legacy of documents recording climatic disasters anddescribing their direct impacts on agriculture and *** the most recent summer precipitation reconstructions and the documentary data,this study presents a systemic analysis of the hydroclimatic anomalies as well as the societal and ecological consequences in China following the1783e1784 CE Laki *** results from multi-proxies show severe drought conditions in eastern China during the post-Laki years,accompanied by large scale locust breakout,famine and human *** drought and associated disasters first emerged in the North ChinaPlain in 1784 CE,intensified and expanded to the middle and lower reaches of the yangtze River in 1785 *** drought and famine stresses inChina are part of the very unsettled climate conditions experienced across the Northern Hemispheric world during the *** isolating theENSO-induced precipitation from the reconstructed summer precipitation changes,our results indicate that the Laki eruption did cause severedrought in monsoon China during the next three *** drought responses in the 1783e1784 were largely counter-balanced by the wettinginduced by the concurring strong El Ni~no *** results help to enhance our understanding of the hydroclimate consequence of NH highlatitude volcanic eruption in China,and the potential role climate interna

关键词： 1783‒1784 CE Laki eruption Hydroclimatic anomalies China El Nino Proxy reconstruction

A new beam element for analyzing geometrical and physical nonlinearity

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Acta Mechanica Sinica 2010年第4期26卷 605-615页

作者： Xiao-Feng Wang Qing-shan yang Qi-Lin Zhang College of Civil Engineering Tongji University 709 Civil Building 1239 Siping Road Shanghai 200092 China School of Civil Engineering Beijing Jiaotong UniversityBeijing 100044 China

Based on Timoshenko＇s beam theory and Vlasov＇s thin-walled member theory, a new model of spatial thin-walled beam element is developed for analyzing geometrical and physical nonlinearity, which incorporates an interior node and independent interpolations of bending angles and warp and takes diversified factors into consideration, such as traverse shear deformation, torsional shear deformation and their coupling, coupling of flexure and torsion, and the second shear stress. The geometrical nonlinear strain is formulated in updated Lagarange （UL） and the corresponding stiffness matrix is derived. The perfectly plastic model is used to account for physical nonlinearity, and the yield rule of von Mises and incremental relationship of Prandtle-Reuss are adopted. Elastoplastic stiffness matrix is obtained by numerical integration based on the finite segment method, and a finite element program is compiled. Numerical examples manifest that the proposed model is accurate and feasible in the analysis of thin-walled structures.

关键词： Spatial beams Thin-walled section Beam element Geometrical and physical nonlinearity FEM