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High-Order DG Schemes with Subcell Limiting Strategies for Simulations of Shocks,Vortices and Sound Waves in Materials Science Problems
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作者 Zhenhua Jiang Xi Deng +3 位作者 Xin Zhang Chao Yan Feng Xiao Jian Yu 《Fluid Dynamics & Materials Processing》 EI 2024年第10期2183-2204,共22页
Shock waves,characterized by abrupt changes in pressure,temperature,and density,play a significant role in various materials science processes involving fluids.These high-energy phenomena are utilized across multiple ... Shock waves,characterized by abrupt changes in pressure,temperature,and density,play a significant role in various materials science processes involving fluids.These high-energy phenomena are utilized across multiple fields and applications to achieve unique material properties and facilitate advanced manufacturing techniques.Accurate simulations of these phenomena require numerical schemes that can represent shock waves without spurious oscillations and simultaneously capture acoustic waves for a wide range of wavelength scales.This work suggests a high-order discontinuous Galerkin(DG)method with a finite volume(FV)subcell limiting strategies to achieve better subcell resolution and lower numerical diffusion properties.By switching to the FV discretization on an embedded sub-cell grid,the method displays advantages with respect to both DG accuracy and FV shock-capturing ability.The FV scheme utilizes a class of high-fidelity schemes that are built upon the boundary variation diminishing(BVD)reconstruction paradigm.The method is therefore able to resolve discontinuities and multi-scale structures on the subcell level,while preserving the favorable properties of the high-order DG scheme.We have tested the present DG method up to the 6th-order accuracy for both smooth and discontinuous noise problems. 展开更多
关键词 Discontinuous Galerkin finite volume subcell limiting shock associated noise computational aeroacoustics
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Internal limiting membrane peeling combined with silicone oil or air tamponade for highly myopic foveoschisis
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作者 Jin Deng Wen-Tao Sun +2 位作者 Ke Gong Li-Ping Wang Feng-Zhi Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第6期1079-1085,共7页
AIM:To compare the efficacy of pars plana vitrectomy(PPV)combined with internal limiting membrane(ILM)and silicone oil or sterile air tamponade for the treatment of myopic foveoschisis(MF)in highly myopic eyes.METHODS... AIM:To compare the efficacy of pars plana vitrectomy(PPV)combined with internal limiting membrane(ILM)and silicone oil or sterile air tamponade for the treatment of myopic foveoschisis(MF)in highly myopic eyes.METHODS:This retrospective study included 48 myopic eyes of 40 patients with MF and axial lengths(ALs)ranging from 26-32 mm treated between January 2020 and January 2022.All patients were underwent PPV combined with ILM peeling followed by sterile air or silicone oil tamponade and followed up at least 12mo.Based on the features on spectral-domain optical coherence tomography(SD-OCT),the eyes were divided into the MF-only group(Group A,n=15 eyes),MF with central foveal detachment group(Group B,n=20 eyes),and MF with lamellar macular hole group(Group C,n=13 eyes).According to AL,eyes were further divided into three groups:Group D(26.01-28.00 mm,n=12 eyes),Group E(28.01-30.00 mm,n=26 eyes),and Group F(30.01-32.00 mm,n=10 eyes).The best-corrected visual acuity(BCVA),central foveal thickness(CFT),and complications were recorded.RESULTS:The patients included 16 males and 24 females with the mean age of 56±9.82y.The BCVA and CFT improved in all groups after surgery(P<0.01),while there was no significant difference of the CFT in Group A,B,and C postoperatively(P>0.05).The intergroup differences of BCVA and CFT postoperatively were statistically significant in Group D,E,and F.Twenty eyes were injected with sterile air,and 28 eyes were injected with silicone oil for tamponade based on the AL.However,there was no statistically significant difference among Groups D,E,and F in terms of the results of sterile air or silicone oil tamponade.The mean recovery time was 5.9mo for MF patients subjected to silicone oil tamponade and 7.7mo for patients subjected to sterile air tamponade,and the difference was not statistically significant.CONCLUSION:PPV and ILM peeling combined with silicone oil or sterile air tamponade can achieve good results for MF in highly myopic eyes with ALs≤32 mm. 展开更多
关键词 axial length myopic foveoschisis highly myopic internal limiting membrane pars plana vitrectomy
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Effects of vitrectomy combined with internal limiting membrane peeling in patients with diabetic macular edema
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作者 Lei Wang Chun-Jie Chen +2 位作者 Ming-Li Wang Yong Huang Li-Jian Fang 《World Journal of Clinical Cases》 SCIE 2024年第21期4491-4498,共8页
BACKGROUND Diabetic macular edema(DME),a chronic microvascular complication of diabetes,is a leading cause of visual impairment and blindness.Pars plana vitrectomy(PPV)can restore the normal macular structure and redu... BACKGROUND Diabetic macular edema(DME),a chronic microvascular complication of diabetes,is a leading cause of visual impairment and blindness.Pars plana vitrectomy(PPV)can restore the normal macular structure and reduce macular edema,whereas internal limiting membrane(ILM)peeling is used to treat tractional macular diseases.Despite the advantages,there is limited research on the combined effects of PPV with ILM peeling.AIM To observe the effects of PPV combined with ILM peeling on postoperative central macular thickness(CMT),best-corrected visual acuity(BCVA),cystoid macular edema(CME)volume,and complications in patients with DME.METHODS Eighty-one patients(92 eyes)diagnosed with DME at the Beijing Shanqu Liangxiang Hospital between January and December 2022 were randomly divided to undergo PPV alone(control group:41 patients,47 eyes)or PPV+ILM peeling(stripping group:40 patients,45 eyes);a single surgeon performed all surgeries.The two groups were compared preoperatively and 1 and 3 months postoperatively.RESULTS Preoperatively,both groups had comparable values of CMT,BCVA,and CME volume(P>0.05).After surgery(both 1 and 3 months),both groups showed significant reductions in CMT,BCVA,and CME volume compared to preoperative levels,with the stripping group showing more significant reductions compared to the control group(P<0.05).Further repeated-measures ANOVA analysis for within-group differences revealed significant effects of group and time,and interaction effects for CMT,BCVA,and CME volume(P<0.05).There were no significant differences in the incidence of complications between the groups(retinal detachment:control=2,stripping=1;endophthalmitis:Control=4,stripping=1;no cases of secondary glaucoma or macular holes;χ^(2)=0.296,P=0.587).CONCLUSION PPV with ILM peeling can significantly improve the visual acuity of patients with DME,reduce CMT,and improve CME with fewer complications. 展开更多
关键词 VITRECTOMY Internal limiting membrane peeling Diabetic macular edema Central macular thickness Bestcorrected visual acuity COMPLICATIONS
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Travel-Limiting Disabilities in the United States: Why Accessibility Matters?
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作者 Oluwaseun Ibukun Bhuiyan Alam 《Journal of Transportation Technologies》 2024年第3期336-357,共22页
This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables o... This study evaluates the distribution of travel-limiting disabilities across genders and geographic locations in the United States. This study aims to describe and compare the socioeconomic and demographic variables of the people with and without travel-limiting disabilities across geographic locations and gender. The study further evaluates the trip purpose and impact of Covid-19 fourth wave pandemic on the use of public transit and travel to physical workplace for the people with and without travel-limiting disabilities across gender and geographic locations. The study uses the 2022 weighted National Household Travel Survey dataset and employs descriptive statistics. Results reaffirm the findings from previous literature that there are more people with travel-limiting disabilities in urban areas and among women. Over 50 percent of people aged 65 and above have a form of travel-limiting disabilities. The most trip for people with travel-limiting disabilities is made for shopping and medical purposes. Across all categories, rural areas, urban areas, male and female for the people without travel-limiting disabilities, COVID-19 fourth wave did not change the pattern of trips made to physical workplace as pre-COVID-19 era. This pattern is also observable for the people with travel-limiting disabilities in rural and urban areas. Females with travel-limiting disabilities reported making less trips to physical workplaces while male reported doing the same as before COVID-19 era. The study concludes that the quantification of travel-limiting disabilities across geographic location and gender is vital in disability study and could drive policy implementation for improved accessibility for the vulnerable population. 展开更多
关键词 National Household Travel Survey United States Travel-limiting Disabilities Descriptive Statistics Covid-19 Disability Study
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A 12 Gbit/s limiting amplifier using 2 GaAs HBT technology for fiber-optic transmission system 被引量:1
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作者 刘欢艳 王志功 +2 位作者 王蓉 冯军 熊明珍 《Journal of Southeast University(English Edition)》 EI CAS 2003年第1期5-7,共3页
A 12 Gbit/s limiting amplifier for fiber-optic transmission system is realized in a 2μm GaAs HBT technology. The whole circuit consists of an input buffer, three similar amplifier cells, an output buffer for driving ... A 12 Gbit/s limiting amplifier for fiber-optic transmission system is realized in a 2μm GaAs HBT technology. The whole circuit consists of an input buffer, three similar amplifier cells, an output buffer for driving 50 ft transmission lines and a pair of feedback networks for offset cancellation. At a positive supply voltage of 2 V and a negative supply voltage of - 2V, the power dissipation is about 280 mW. The small-signal gain is higher than 46 dB and the input dynamic range is about 40 dB with a constant single-ended output voltage swing of 400 mV. Satisfactory eye-diagrams are obtained at the bit rate of 12 Gbit/s limited by the test set-up. The chip area is 1.15 mm ×0.7 mm. 展开更多
关键词 optical receiver limiting amplifier GaAs HBT technology
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Nutrient Limiting Factor and Agronomic Efficiency of Wheat in Fluvo-aquic Soil District in Northwest of Shandong Province 被引量:1
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作者 马征 魏建林 +4 位作者 郭洪海 张柏松 董晓霞 徐长英 崔荣宗 《Agricultural Science & Technology》 CAS 2013年第8期1191-1194,共4页
[Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set ... [Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set in order to explore the effects of fertilizer recommendation based on ASI systematic approach on wheat yield,agronomic efficiency and recovery rate of nutrients.[Result] Nitrogen was the main limiting factor for wheat production in that area,followed by phosphorus,and the third was potassium.Compared with the optimum treatment (OPT),the reduction of N,P and K reduced the grain yield obviously,which came up to 22.4%,14.4% and 13.4% respectively.There were no obvious differences in grain yield among Farmer's Fertilization Practice (FP),60% OPT-N and OPT treatment.[Conclusion] Agronomic efficiency of N,P and K was 6.3,12.9 and 10 kg/kg respectively.The recovery rates of N,P and K in wheat season were 16.41%,17.27% and 27.27% respectively. 展开更多
关键词 WHEAT Fluvo-aquic soil YIELD Nutrient limiting factor Agronomic efficiency
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Climatic Factors for Limiting Northward Distribution of Eight Temperate Tree Species in Eastern North America 被引量:3
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作者 方精云 李莹 《Acta Botanica Sinica》 CSCD 2002年第2期199-203,共5页
Eight temperate deciduous tree species, Acer rubrum L., A. saccharinum L., A. saccharum Marsh., Belluta alleghaniensis Britton., Fraxinus nigra Marsh., Quercus rubra L., Titia americana L., and Ulmus americana L. in e... Eight temperate deciduous tree species, Acer rubrum L., A. saccharinum L., A. saccharum Marsh., Belluta alleghaniensis Britton., Fraxinus nigra Marsh., Quercus rubra L., Titia americana L., and Ulmus americana L. in eastern North America, were selected to explore relationship between the northward distribution of temperate tree species and climatic factors. For each species, more than 30 sites at their north limits of distribution were obtained from their distribution maps, and 11 climatic indices at the north limits were computed. The standardized standard deviation (SD) method, which compares the magnitude of variance of climatic indices, was used to detect which climatic parameter was the most important for explaining northward distribution of these species. We presume that the climatic parameter that has the smallest variance at the north limit would be assigned as the dominant climatic factor for limiting the distribution of this species. The results derived from the standardized SD method indicated that the SD value of warmth index (WI) and/or annual biotemperature (ABT) were the smallest among the 11 climatic indices. Since both WI and ABT represent growing season temperature, it suggested that growing season temperature was the most important climatic factor for explaining the northward distribution of these temperate tree species. The relationships between several climatic indices, WI, coldness index (CI), annual precipitation (AP), annual range of temperature (ART) and humid/arid index were also analyzed. As a result, at the north limits of all these species, both WI and CI decreased with an increase of AP, and CI increased with an increase of ART. Besides growing season temperature, precipitation and climatic continentality also have influence on the northward distribution of the temperate trees in eastern North America. 展开更多
关键词 eastern North America northward limit of distribution climatic index growing season temperature precipitation standard deviation
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A Novel Polysilicon and Oxide Sandwich Deep Trench with Field Limiting Ring for RF Power Transistors
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作者 齐臣杰 傅军 +1 位作者 王军军 刘理天 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第11期1398-1402,共5页
A vertical sandwich deep trench with a field limiting ring is proposed to improve the breakdown voltage of power devices and high voltage devices.Simulation result shows that nearly 100% breakdown voltage of the plane... A vertical sandwich deep trench with a field limiting ring is proposed to improve the breakdown voltage of power devices and high voltage devices.Simulation result shows that nearly 100% breakdown voltage of the plane junction can be realized. 展开更多
关键词 deep trench field limiting ring breakdown voltage
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5Gb/s 0.25μm CMOS Limiting Amplifier
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作者 胡艳 王志功 +1 位作者 冯军 熊明珍 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2003年第12期1250-1254,共5页
A limiting amplifier (LA) IC implemented in TSMC standard 0.25μm CMOS technology is described.Active inductor loads and direct-coupled technology are employed to increase the gain,broaden the bandwidth,reduce the pow... A limiting amplifier (LA) IC implemented in TSMC standard 0.25μm CMOS technology is described.Active inductor loads and direct-coupled technology are employed to increase the gain,broaden the bandwidth,reduce the power dissipation,and keep a tolerable noise performance.Under a 3.3V supply voltage,the LA core achieves a gain of 50-dB with a power consumption below 40mW.The measured input sensitivity of the amplifier is better than 5m V _ pp .It can operate at bit rates up to 7Gb/s with an rms jitter of 0.03 UI or less.The chip area is only 0.70mm×0.70mm.According to the measurement results,this IC is expected to work at the standard bit rate levels of 2.5,3.125,and 5Gb/s. 展开更多
关键词 limiting amplifier active inductor shunt peaking technique CMOS
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A 155Mbps 0.5μm CMOS Limiting Amplifier
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作者 焦阳 王志功 +1 位作者 王蓉 管志强 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第2期176-181,共6页
This paper presents a 155Mbps limiting amplifier for STM-1 systems of SDH optical communication. It is implemented in CSMC 0.5μm CMOS technology. Under a supply voltage of 3.3V, it has a power consumption of 198mW. T... This paper presents a 155Mbps limiting amplifier for STM-1 systems of SDH optical communication. It is implemented in CSMC 0.5μm CMOS technology. Under a supply voltage of 3.3V, it has a power consumption of 198mW. The core of the circuit is composed of 6 cascaded amplifiers that are in a conventional structure of differential pairs,an output buffer, and a DC offset cancellation feedback loop. The small signal gain can be adjusted from 74 to 44dB by an off-chip resistor. The chip was packaged before being tested. The experimental results indicate that the circuit has an input dynamic range of 54dB and provides a single-ended output swing of 950mV. Its output eye diagram remains satisfactory when the pseudo-random bit sequence (PRBS) input speed reaches 400Mbps. 展开更多
关键词 optical communication limiting amplifier CMOS technology SDH
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Spatial-Temporal Distribution Characteristics and Limiting Factors of Medium-low Yield Farmland in Tianjin
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作者 潘洁 吕雄杰 +1 位作者 肖辉 陆文龙 《Agricultural Science & Technology》 CAS 2015年第3期578-582,共5页
[Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [... [Objective] This paper aimed to understand the area change and distribu- tion of medium-low yield farmland, and offered basis to the improvement of mediumlow farmland and its increase of grain production in Tianjin. [Method] Based on the statistical date of Tianjin and its relevant counties and districts, the yield standard was set up to classify high-yield, medium-yield and low-yield farmland in Tianjin. The author analyzed area change of medium-low yield farmland in six agricultural counties and districts (including Jixian County, Wuqing District, Baodi District, Ninghe County, Jinghai County and Dagang district of Binghai New Area) from 1980 to 2010. [Result] The results showed that the average yield of grain rose from 2 445 kg/hm^2 in 1980 to 5 130 kg/hm^2 in 2010, increasing 109.82%. The area of mediumlow yield farmland was reduced from 291 250.13 hm^2 in 1985 to 76 489.87 hm^2 in 2010, coming down 74%. In Tianjin, the area of medium-low yield farmland of 2010 accounted for 19% of the total farmland, of which the ratios of medium-low yield farmland of Jinghai County, Jixian County, Dagang district of Binghai New Area, Wuqing District, Baodi District and Ninghe County were 43.12%, 18.59%, 17.23%, 14.01%, 7.05% and 0, respectively. Low soil nutrient content, drought and water shortage, as well as soil salinization were the main yield limiting factors to mediumlow yield farmland in Tianjin in 2010. [Conclusion] The countermeasures to improve the medium-low yield farmland were proposed, involving enhancing the investment of the government, strengthening the construction of water conservancy infrastructure, further improving the soil fertility, as well as saline and alkaline land, optimizing the farming system and planting drought and salt tolerance crops, etc. 展开更多
关键词 Medium-low yield farmland Spatial-temporal distribution limiting factors TIANJIN
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A New Quasi 2-Dimensional Analytical Approach to Predicting Ring Junction Voltage,Edge Peak Fields and Optimal Spacing of Planar Junction with Single Floating Field Limiting Ring Structure
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作者 何进 张兴 +1 位作者 黄如 王阳元 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第6期700-705,共6页
WT8.BZ]A new quasi 2-dimensional analytical approach to predicting the ring voltage,edge peak fields and optimal spacing of the planar junction with a single floating field limiting ring structure has been proposed,ba... WT8.BZ]A new quasi 2-dimensional analytical approach to predicting the ring voltage,edge peak fields and optimal spacing of the planar junction with a single floating field limiting ring structure has been proposed,based on the cylindrical symmetric solution and the critical field concept.The effects of the spacing and reverse voltage on the ring junction voltage and edge peak field profiles have been analyzed.The optimal spacing and the maximum breakdown voltage of the structure have also been obtained.The analytical results are in excellent agreement with that obtained from the 2-D device simulator,MEDICI and the reported result,which proves the presented model valid. 展开更多
关键词 floating field limiting ring breakdown voltage edge peak electric filed ring spacing
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Effects of Limiting Amino Acids on Rumen Fermentation and Microbial Community In vitro 被引量:17
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作者 WANG Meng-zhi WANG Hong-rong CAO Heng-chun LI Guo-xiang ZHANG Jie 《Agricultural Sciences in China》 CAS CSCD 2008年第12期1524-1531,共8页
Three goats fitted with cannula were used to provide rumen liquor to investigate the effects of limiting amino acids on rumen fermentation and microbial community in vitro. The removal method was used in the current e... Three goats fitted with cannula were used to provide rumen liquor to investigate the effects of limiting amino acids on rumen fermentation and microbial community in vitro. The removal method was used in the current experiments. Treatments are total essential amino acid (TEAA), His-removal, Lys-removal, Met-removal, and branch chain amino acid (BCAA)- removal. Results indicated that, pH-value ranged between 5.9 and 6.8, with the highest mean value for the group with BCAA-removal (6.54) in the culture. Concentration of NH3-N ranged between 10.99 to 30.51 mg 100 mL^-1, with the group of TEAA recording the highest average NH3-N concentration (17.85 mg 100 mL^-1). Yields of microbial protein and limiting degree on microbial growth varied with treatments (P 〈 0.01), and the lowest accrued in treatment with BCAA-removal (0.1389, 0.1772, and 0.3161 mg mL^-1 for bacteria, protozoa, and mixed microbes, respectively), compared to the group with TEAA, microbial production of mixed microbes decreased by 44.52%. As for micro-flora, protozoa to bacteria ratio was the lowest for the group with Lys-removal (89.12%), while the highest for the group with BCAA-removal (127.60%) (P 〈 0.01). Furthermore, PCR-SSCP analysis revealed that, microbial profile subjected to substrates within bacteria and protozoa groups. It was therefore concluded that, dietary amino acid influenced both rumen fermentation and microbial characteristics. 展开更多
关键词 limiting amino acids rumen microbes limiting degree
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Identifying the limiting factors driving the winter wheat yield gap on smallholder farms by agronomic diagnosis in North China Plain 被引量:10
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作者 CAO Hong-zhu LI Ya-nan +3 位作者 CHEN Guang-feng CHEN Dong-dong QU Hong-rui MA Wen-qi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第8期1701-1713,共13页
North China Plain(NCP) is the primary winter wheat production region in China, characterized by smallholder farming systems. Whereas the winter wheat average yield of smallholder farmers is currently low, the yield po... North China Plain(NCP) is the primary winter wheat production region in China, characterized by smallholder farming systems. Whereas the winter wheat average yield of smallholder farmers is currently low, the yield potential and limiting factors driving the current yield gap remain unclear. Therefore, increasing the wheat yield in NCP is essential for the national food security. This study monitored wheat yield, management practices and soil nutrient data in 132 farmers’ fields of Xushui County, Baoding City, Hebei Province during 2014–2016. These data were analyzed using variance and path analysis to determine the yield gap and the contribution of yield components(i.e., spikes per hectare, grain number per spike and 1 000-grain weight) to wheat yield. Then, the limiting factors of yield components and the optimizing strategies were identified by a boundary line approach. The results showed that the attainable potential yield for winter wheat was 10 514 kg ha^–1. The yield gaps varied strongly between three yield groups(i.e., high, middle and low), which were divided by yield level and contained 44 farmers in each group, and amounted to 2 493, 1 636 and 814 kg ha^–1, respectively. For the three yield components, only spikes per hectare was significantly different(P<0.01) among the three yield groups. For all 132 farmers’ fields, correlation between yield and spikes per hectare(r=0.51, P<0.01), was significantly positive, while correlations with grain number per spike(r=–0.16) and 1 000-grain weight(r=–0.10) were not significant. The path analysis also showed that the spikes per hectare of winter wheat were the most important component to the wheat yield. Boundary line analysis showed that seeding date was the most limiting factor of spikes per hectare with the highest contribution rate(26.7%), followed by basal N input(22.1%) and seeding rate(14.5%), which indicated that management factors in the seeding step were the most important for affecting spikes per hectare. For desired spikes per hectare(>6.598×10^6 ha^–1),the seeding rate should range from 210–300 kg ha^–1, seeding date should range from 3th to 8th October, and basal N input should range from 90–180 kg ha^–1. Compared to these reasonable ranges of management measures, most of the farmers’ practices were not suitable, and both lower and higher levels of management existed. It is concluded that the strategies for optimizing yield components could be achieved by improving wheat seeding quality and optimizing farmers’ nutrient management practices in the NCP. 展开更多
关键词 yield GAPS SMALLHOLDER limiting factors path ANALYSIS boundary line ANALYSIS
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Inverted internal limiting membrane flap technique for very large macular hole 被引量:11
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作者 Mitali Khodani Pooja Bansal +1 位作者 Raja Narayanan Jay Chhablani 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第8期1230-1232,共3页
AIMTo assess the anatomical and visual outcome of idiopathic macular holes greater than 1000 &#x000b5;m using the inverted internal limiting membrane flap technique.METHODSThis retrospective case series included 5... AIMTo assess the anatomical and visual outcome of idiopathic macular holes greater than 1000 &#x000b5;m using the inverted internal limiting membrane flap technique.METHODSThis retrospective case series included 5 eyes of 5 patients with idiopathic macular hole with base diameter greater than 1000 &#x000b5;m who underwent inverted internal limiting membrane flap technique along with standard 23G pars plans vitrectomy with posterior hyaloid detachment and fluid gas exchange with 12%-14% perfluoropropane (C3F8). Preoperative and postoperative visual acuity and spectral domain optical coherence tomography images were evaluated. The main outcome measures were visual outcome and macular hole closure.RESULTSMean age was 63.2&#x000b1;8.4y with all 5 subjects being females. Mean duration of symptoms was 11&#x000b1;14mo with a mean postoperative follow up of 13.2&#x000b1;13mo. The mean base diameter of the macular holes was 1420&#x000b1;84.8 &#x000b5;m (1280-1480 &#x000b5;m). Type 1 closure was achieved in four out of five patients, while one patient had type 2 closure using the inverted internal limiting membrane (ILM) flap technique. Median baseline BCVA was 0.79 logMAR (Snellen’s equivalent 20/120) and median final BCVA 0.6 logMAR (Snellen’s equivalent 20/80) with mean visual improvement of approximately three lines improvement. No complications related to surgical procedure were noted.CONCLUSIONThe inverted internal limiting membrane flap technique may be promising for very large macular holes with high rate of macular closure and good visual outcome. 展开更多
关键词 inverted internal limiting membrane flap technique VITRECTOMY macular hole
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EXAMINATION OF SILICATE LIMITATION OF PRIMARY PRODUCTION IN JIAOZHOU BAY, CHINA I. SILICATE BEING A LIMITING FACTOR OF PHYTOPLANKTON PRIMARY PRODUCTION 被引量:31
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作者 杨东方 张经 +2 位作者 吕吉斌 高振会 陈豫 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2002年第3期208-225,共18页
Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations i... Jiaozhou Bay data collected from May 1991 to February 1994, in 12 seasonal investigations, and provided the authors by the Ecological Station of Jiaozhou Bay, were analyzed to determine the spatiotemporal variations in temperature, light, nutrients (NO - 3 N, NO - 2 N, NH + 4 N, SiO 2- 3 Si, PO 3- 4 P), phytoplankton, and primary production in Jiaozhou Bay. The results indicated that only silicate correlated well in time and space with, and had important effects on, the characteristics, dynamic cycles and trends of, primary production in Jiaozhou Bay. The authors developed a corresponding dynamic model of primary production and silicate and water temperature. Eq.(1) of the model shows that the primary production variation is controlled by the nutrient Si and affected by water temperature; that the main factor controlling the primary production is Si; that water temperature affects the composition of the structure of phytoplankton assemblage; that the different populations of the phytoplankton assemblage occupy different ecological niches for C , the apparent ratio of conversion of silicate in seawater into phytoplankton biomas and D , the coefficient of water temperature’s effect on phytoplankton biomass. The authors researched the silicon source of Jiaozhou Bay, the biogeochemical sediment process of the silicon, the phytoplankton predominant species and the phytoplankton structure. The authors considered silicate a limiting factor of primary production in Jiaozhou Bay, whose decreasing concentration of silicate from terrestrial source is supposedly due to dilution by current and uptake by phytoplankton; quantified the silicate assimilated by phytoplankton, the intrinsic ratio of conversion of silicon into phytoplankton biomass, the proportion of silicate uptaken by phytoplankton and diluted by current; and found that the primary production of the phytoplankton is determined by the quantity of the silicate assimilated by them. The phenomenon of apparently high plant nutrient concentrations but low phytoplankton biomass in some waters is reasonably explained in this paper. 展开更多
关键词 PHYTOPLANKTON silicon limiting factor Jiaozhou Bay
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Treatment of refractory giant macular hole by vitrectomy with internal limiting membrane transplantation and autologous blood 被引量:6
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作者 Wen-Juan Lyu Lei-Bing Ji +2 位作者 Yun Xiao Yin-Bo Fan Xue-Hong Cai 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第5期818-822,共5页
AIM:To investigate the effect of internal limiting membrane transplantation and autologous blood on treating refractory giant macular hole.METHODS:Thirty-seven eyes with giant macular hole of the smallest hole diame... AIM:To investigate the effect of internal limiting membrane transplantation and autologous blood on treating refractory giant macular hole.METHODS:Thirty-seven eyes with giant macular hole of the smallest hole diameter 〉700 μm,the maximum diameter of the substrate 〉1000 μm and hole formation factor 〈0.6 underwent surgical treatment.The patients were randomly divided into two groups.Nineteen eyes with surgical flip of the internal limiting membrane in group A,18 eyes with internal limiting membrane transplantation in group B who underwent the tamponade of internal limiting membrane into the hole,autologous plasma was used to seal the hole.The patients were followed up for 3 mo,optical coherence tomography and best corrected visual acuity(BCVA) were recorded before and after operation,and the results were statistically analyzed.RESULTS:At 3 mo after operation,BCVA of the two groups was significantly improved compared with that before operation(tA=4.192,tB=4.374,P〈0.05).But there was no significant difference in visual acuity between the two groups(χ^2=0.128,P〉0.05).At 3 mo after operation,the closure rate of group A was 68.4%,and 100% in group B.(χ^2=5.628,P〈0.05).The defect diameter of inner segment/outer segment at 3 mo after the operation was significantly lower than that before operation(tA=12.287,tB=15.481,P〈0.05),and the difference was statistically significant(t=2.552,P〈0.05).CONCLUSION:Internal limiting membrane transplantation combined with autologous whole blood can improve the postoperative closure rate of the refractory large aperture,and can effectively improve the postoperative visual acuity. 展开更多
关键词 internal limiting membrane transplantation autologous blood REFRACTORY macular hole
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Combine intravitreal bevacizumab with Nd: YAG laser hyaloidotomy for valsalva pre-macular haemorrhage and observe the internal limiting membrane changes: a spectralis study 被引量:3
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作者 Rui Hua Li-Min Liu +2 位作者 Yue-Dong Hu Yun Zhou Lei Chen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第2期242-245,共4页
Valsalva retinopathy was described as a particular form of retinopathy, pre-retinal and subinternal limiting membrane haemorrhages in nature that rarely may break through and become subhyloid or intravitreal, secondar... Valsalva retinopathy was described as a particular form of retinopathy, pre-retinal and subinternal limiting membrane haemorrhages in nature that rarely may break through and become subhyloid or intravitreal, secondary to a sudden increase in intrathoracic pressure. We reported a new way that Nd:YAG laser for ILM hyaloidotomy in order to drain the sub-ILM blood into vitreous cavity combined with intravitreal bevacizumab to improve the absorption of blood. Therapeutic alliance make significant outcome, protecting vision in time. We used spectralis OCT to observe sub-ILM mix cells and special ILM structure in this lesion for the first time, as the spectralis OCT can reach histology level imagination. 展开更多
关键词 valsalva retinopathy spectralis OCT internal limiting membrane BEVACIZUMAB
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Efficacy and safety of vitrectomy with internal limiting membrane peeling for diabetic macular edema: a Meta-analysis 被引量:7
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作者 Xin-Ying Hu Huan Liu +2 位作者 Li-Na Wang Yu-Zhi Ding Jie Luan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第11期1848-1855,共8页
AIM: To evaluate the efficacy and safety of vitrectomy with internal limiting membrane(ILM) peeling for diabetic macular edema(DME). METHODS: The PubMed, Embase, Web of Science, Cochrane, SionMed, ClinicalTrials... AIM: To evaluate the efficacy and safety of vitrectomy with internal limiting membrane(ILM) peeling for diabetic macular edema(DME). METHODS: The PubMed, Embase, Web of Science, Cochrane, SionMed, ClinicalTrials.gov, CNKI databases and Wanfang databases, published until Oct. 2017, were searched to identify studies comparing the clinical outcomes following vitrectomy with and without ILM peeling, for treating DME. Pooled results were expressed as odds ratios(ORs) with corresponding 95% confidence intervals(CI) for vitrectomy with and without ILM peeling with regard to best corrected visual acuity(BCVA), central macular thickness(CMT), and complication incidents. RESULTS: A total of 14 studies involving 857 eyes were included of which three studies were Chinese and the rests were English literatures. Meta-analysis indicated that compared with vitrectomy alone, vitrectomy with ILM peeling could improve BCVA more obviously(OR=1.66, 95%CI: 1.12-2.46, P=0.01) and had higher rate of CMT reduction(OR=3.89, 95%CI: 1.37-11.11, P=0.01). There were significant statistical differences between the two surgical methods for both BCVA and CMT(P〈0.05). For the incidence of intraoperative and postoperative complications, the incidence of epiretinal membrane(ERM) was slightly lower in the ILM peeling group than the group without ILM peeling(OR=0.38, 95%CI: 0.07-2.00, P=0.25), although insignificant statistically. Other incidences of overall complications, iatrogenic peripheral retinal break and increased intraocular pressure indicated no significant difference between two groups(OR=1.19, 95%CI: 0.82-1.73, P=0.36; OR=1.21, 95%CI: 0.66-2.21, P=0.53; OR=1.34, 95%CI: 0.75-2.40, P=0.32). CONCLUSION: Vitrectomy is effective for DME and the effect can be improved by additional ILM peeling, especially for anatomical efficacy, without increasing the incidence of intraoperative and postoperative complications. However, it is imperative to gain more evaluation in the future due to the paucity of prospective randomized study. 展开更多
关键词 internal limiting membrane vitrectomy diabetic macular edema META-ANALYSIS
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Free autologous internal limiting membrane transplantation in the treatment of large macular hole 被引量:2
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作者 Fei-Yan Ma Rui-Jie Xi +1 位作者 Peng-Fei Chen Yu-Hua Hao 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第5期848-851,共4页
We evaluated the clinical efficacy of free internal limiting membrane(ILM) flap transplantation for the treatment of large macular hole over 500 μm in 42 consecutive patients. Quantified evaluation of the post-operat... We evaluated the clinical efficacy of free internal limiting membrane(ILM) flap transplantation for the treatment of large macular hole over 500 μm in 42 consecutive patients. Quantified evaluation of the post-operative macular anatomy restoration was performed by spectral-domain optical coherence tomography in the 12 mo follow-up. The results showed 41 eyes achieved successful closure(97.6%). Postoperative best corrected visual acuity, ellipsoid layer, and external limiting membrane disruption were significantly improved at all follow-up time points. The central foveal thickness was significantly higher at 1 mo. We concluded that free ILM flap transplantation proves to be effective to achieve anatomical and functional improvement for the treatment of large macular hole. 展开更多
关键词 vitreoretinal disease MACULAR HOLE internal limiting membrane VITRECTOMY
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